Apparatus for burning sulphur



Aug. 8, 1933.

L. GILLETT APPARATUS FOR BURNING SULPHUR Filed Fb. 10, 1927 sublimer INVENTOR ATTORNEY :25 in the process.

Patented, Aug. 8, 1933 PA NroFFICE APP RATUS FOR BURNING SULPHUR.

Lowry Gillett, Syossett, N. Y., assignor to Gen-g v eral Chemical Company; New York, N.'Y., a

' Corporation o'f NeW Yrk Application February 10, 1927. Serial No. 167,344

Claims. (01. 2s--27s) This invention relates to an apparatus for burning sulphur in which the sulphur. is first .sublimed in a molten sulphur container and the sublimed'sulphur is then completely burned in a combustion chamber. More particularly the invention relates to the means for supplying air' to the sublimer'and combustion chamber of ap- V paratus of this type.

i In apparatus of this general nature a main blower isused to supply air to the combustion chamber and separate booster blower is' used to supply air to the sublimer. Each of the blowers has an independent control whichis arranged to be manually operated. As a result either of the blowers will continue town .after the other '20 Such operation would result in sulphur being sublimed and passed into and through the combustionchamber without burning. The unburned sublimed sulphur would choke up the combustion chamber and apparatus further on When utilizing the sulphur burnerv for example as a source of sulphur dioxide gas for a contact sulphuric acid system the unburned sulphur is'liable to cause serious contamination of the remainder of the system and possibly cause poisoning of the platinum catalyst.

It is the purpose of this invention to prevent such internal injury to the apparatus by so controlling the booster blower, that it can only operate when the main blower is operating, and thus providing that air cannot be supplied to the sublimer unless the air for combustion is at the same time being supplied to the combustion chamber.

Referring to the accompanying drawing in which the figure is a diagrammatic illustration of one. form of the invention, the apparatus consists essentially of a' sulphur sublimer 1 adapted to contain a body of molten sulphur, a combustion chamber 2, blowers 11 and 8 for supplying air to the sublimer and combustion chamber, respectively, and a control. system at 3, for the air supply to the apparatus.

The sulphur is fed from a hopper 4 by means of a screw conveyor 5 to thesublimer 1. Here it becomes molten and then the'larger portion of it is sublimed by the heat generated in burning a smaller portion. The conveyor 5, which is driven by means such as the gear 6, is controlled so that the molten sulphur always maintains a. predetermined level in the sublimer. If necessary, means (not shown) can be provided ".to'actas a seal to prevent the gases in the sublimerfrom escaping through the hopperi;

The air for the system is supplied by a main 0 blower 8 from which it is'passed through .a pipe '9 to the combustion chamber 2; Pipe 9:is tapped at 10 to supply air to the separate booster blower 11. The booster blower in turn furnishes air at zahigher pressure than the main blower to the sublimer 1' through a pipe 12. It is necessary to; have the air pressure 'to the sublimer. higher than that to the combustion chamber in order to force the air through the molten sulphur and the resulting gases into the combustion chamber.

A distributing member 13, placed under the surface of the sulphur in the sublimer is connected to the pipe 12; By means of thismember13 the air from the. booster blower is distributed in aplurality ofstreams under the surface of the molten sulphur. The oxygen in the. air

combines with the sulphur by a highly. exothermic reaction toform a comparatively small amount of sulphur dioxide.

phur practically all the heat resulting therefrom is utilized in subliming a comparatively large proportion of the sulphur. The S02 gas and the sublimed sulphur are' forced by the high booster blower pressure from the sublimer to the combustion chamber 2 through the pipe 14. 1 In chamber 2 the air from the main blower is mixed with the sublimed sulphur and the complete combustion of the sulphur then occurs; A major proportion of the S02 gas is formed in this chamber, the remainder coming from the sublimer. 'The gases are passed by pipe 15 to the next step of the process. I V

The main blower and the booster blower are driven by electric motors diagrammatically represented at 16 and 17 respectively. Motor 16 is connected to the feed. lines 251 by a circuit 18 1 containing the starting box 19. Motor 17 is connected through a circuit 20 containing. a. starting box 21, to. the same feed lines. A solenoid 22, whose core actuates a switch 23, is shunted across the circuit 18 between the starting box and the motor so that the solenoid is energized and the switch closed when the motor 16 is running. When the motor circuit 18 is broken the switch opens automatically The switch 23 is located in the circuit 20 between the starting box and the feed lines. Bythis As this reaction 80 takes place under the surface of theimolten sularrangement the. circuit 20 for the motor 1'7 can .be completed only when the motor 16 is running and if at any time the motor 16 is stopped the circuit for motor 17 is broken automatically.

The operation is as follows:

Air is supplied to the combustion chamber from the main blower and to the sublimer from the booster blower. The oxidation of the sulphur in the sublimer to sulphur dioxide generates sufficient heat to sublime or volatilize the remaining sulphur, and the gas thus produced containing a minor proportion of sulphur dioxide and a major proportion of sulphur vapor passes from the sublimer to the combustion chamber where it is mixed with the air from the main blower. The complete combustion of the sublimed sulphur then takes place in the com bustion chamber.

The main blower is controlled by starting box 19. This starting box also controls through solenoid 22, the feed to the second starting box 21. The booster blower is controlled by the second starting box. As a result the booster blower cannot be operated and air cannot be supplied. to the sublimer when the circuit for the main blower is not completed. Or in other words air cannot. be supplied to the sublimer when air is not being supplied to the combustion chamber. This arrangement makes it impossible for unburned sulphur to pass through the combustion chamber .or to accumulate therein due to faulty operation of the main blower, and thus accomplishes the results desired.

It is not essential that the control means which shut off the supply of'air to the sublimer whenever the supply of air to the combustion chamber ceases, shall be of an electric or electromagnetic character. Thus, for example, a valve in the air line 12 could be mechanically operated by the mechanism of the blower 8 or by .the air pressure in the line 9 in such a way as to prevent the flow of air through 12, except when the blower 8 is functioning or when there is pressure from the blower 8 in the line 9.

.By the term sublimer as used in the appended claims I intend to include any type of sulphur sublimer or burner producing a gas containing substantial amounts of sulphur. vapor or unburned sulphur which must be subsequently burned with additional air or oxygen.

I claim:

1. An apparatus for burning sulphur comprising a sublimer adapted to contain a body of molten sulphur, a combustion chamber connected to said sublimer, a main blower for supplying air under pressure to said combustion chamber, a booster blower feeding from the main blower for introducing air under the surface of the sulphur in the sublimer at a pressure greater than that at which air is supplied to the combustion chamber by the main blower, an electric circuit including a motor and starting box for said main blower, a similar circuit for said booster blower, and means controlled by said first-named circuit acting on cessation of power input to the main blower to stop the power input to the booster blower.

2. An apparatus for burning sulphur comprising a sublimer, means for maintaining a pool of molten sulphur in the sublimer at a predetermined level, an air distributor positioned beneath the surface level of the molten sulphur, a combustion chamber connected to the gas outlet of the sublimer, a main blower for feeding air under pressure to the combustion chamber, a booster blower for feeding air to the air distributor in the sublimer and operating to deliver air to the distributor at pressures higher than that at which air is fed into. the combustion chamber by the main blower and in quantities such that only a small amount of sulphur is burned and the heat generated thereby is utilized to sublime the remaining sulphur, an electric circuit including a motor and a starting box for operating the main blower, and a similar circuit for the booster blower, and a circuit breaker in the second-named circuit controlled by thefirst-named circuit and acting on cessation of power input to the'main blower to stop the power input to the booster blower.

LOWRY GILLETT. 

